DESCRIPTION: (Adapted from the applicant's description) This application requests partial support for the Ninth International Workshop on the Molecular Biology of Chromosome 21. The workshop will be held on September 23-26, 2000, at The Jackson Laboratory in Bar Harbor, Maine. The purpose of the workshop is to bring together investigators with a broad spectrum of research interests to discuss the current state of knowledge regarding Down syndrome and human chromosome 21. Content of this year will include completion of the chromosome 21 sequence, genome structure and gene discovery, parallel studies of cognition and behavior in Down syndrome and mouse models for Down syndrome, as well as mouse models for selected single gene diseases associated with human chromosome 21.